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9,253 diagnostic guides
Find codes by symptomChoose what you notice to search matching code guides.
Rough idle or shakingVibration while stoppedHard to startLong cranking or no-startEngine stallsCuts out at idle or on the roadHesitates or loses powerSlow response when acceleratingBattery light is onCharging system warningHarsh gear changesDelayed or rough shifting
A symptom can have several causes. Treat matching codes as clues and follow the diagnostic checks in each guide.
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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.
Diagnostic codes
Showing 3457–3480 of 8256
P2027EVAP Fuel Vapor Temperature Sensor Circuit High VoltageCheck soonEmissions System30–120 minutes for initial diagnosisP2029Fuel Fired Heater DisabledCheck soonFuel System30–120 minutes for initial diagnosisP202AReductant Tank Heater Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP202BReductant Tank Heater Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP202CReductant Tank Heater Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP202DReductant LeakageCheck soonSensors & Electronics30–120 minutes for initial diagnosisP202EReductant Injection Valve Circuit Range/Performance Bank 1 Unit 1Check soonFuel System30–120 minutes for initial diagnosisP202FReductant/Regeneration Supply Control Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2030Fuel Fired Heater PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2031Exhaust Gas Temperature Sensor Circuit Bank 1 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP2032Exhaust Gas Temperature Sensor Circuit Low Bank 1 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP2033Exhaust Gas Temperature Sensor Circuit High Bank 1 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP2034Exhaust Gas Temperature Sensor Circuit Bank 2 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP2035Exhaust Gas Temperature Sensor Circuit Low Bank 2 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP2036Exhaust Gas Temperature Sensor Circuit High Bank 2 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP2037Reductant Injection Air Pressure Sensor A CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2038Reductant Injection Air Pressure Sensor A Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2039Reductant Injection Air Pressure Sensor A Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP203AReductant Level Sensor A CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP203BReductant Level Sensor A Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP203CReductant Level Sensor A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP203DReductant Level Sensor A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP203EReductant Level Sensor A Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP203FReductant Level Too LowCheck soonSensors & Electronics30–120 minutes for initial diagnosis